Method of and apparatus for injecting medicated solutions



Feb. 24, i 1931. p, 'n1-Us 1,794,215 METHOD 0F AND APPARATUS FORINJECTING MEDICATED soLTIQNs Filed vJune 14, 1928 2 Sheets-Sheet lINVENTOR Feb. 24, 1931. P. 'rrrus 1,794,215

METHOD OF AND APPARATUS FOR INJECTING MEDICATED SOLUTIONS Filed June 14,1928 2 Sheets-Sheet 2 4 E 300C: f l

3 250m a l J4 Ei zooc" El; 2 |5ocl r-l Q, 50cl OPEN a I2 Patented Feb.24, 1931 UNITED STATES PATENT OFFICE PAUL TITUS, OF PITTSBURGH,PENNSYLVANIA Application led .Tune 14,

This invention relates generally to a method of and apparatus forinjecting medicated solutions, and particularly to the intravenousinjection of dextrose solutions.

In one clinic with which the inventor is connected, dextrose solutionsin the amount of 20,000 cc. per month are being injected intravenously.In spite. of the fact that such large quantities of medicated solutionsare being regularly employed in many clinics, a common and frequentlyharmful mistake in the intravenous administration of such solutions isthat the solutions are administered too rapidly. It is a fact in themajority of clinics certain known physiological fact-s as to the rate atwhich the body is able to take up and utilize injected dextrosesolutions are almost totally disregarded, with the result that dosagebecomes inaccurate, large amounts of the medicine are wasted by beingexpelled through the kidneys and the expected therapeutic effect is thusvitiated in direct ratio to the speed at which the injection is given.It is probable, moreover, that this is also a common cause of certainunfavorable reactions which occur following dextrose injections.

It has been previously determined that an individual can utilize .8 gramof injected dextrose per hour for each kilogram of body weight, and thatto give more than this amount by injecting` a solution too rapidlysimply results in the excretion of the solution from the body andproportionate loss of its medicinal action.

Based on many experiments, the average single dose of dextrose givenintravenously to an average sized adult (150 pounds or 56 kilograms)should be 7 5 grams. In most 1nstances it is preferred to usethedextrose 1n a 25% solution, and such solution may be produced bydissolving grams of dextrose in 300 cc. of freshly double distilledwater.

Bearing in mind that the average individual can uitilize up to .8 gramof dextrose per kilogram of body weight per hour, it will be apparentthat a 25% solution of dextrose should be injected into an average sizedadult (56 kilograms) at a maximum rate .of 3 cc. per minute. A slowerrate of flow will even- 1928. Serial No. 285,301.

tually give the patient his full dose at an absorbable rate, but afaster rate will simply result in theloss by elimination of the surplusfrom the body. A full dose of a 25% dextrose solution formed bydissolving 7 5 grams of dextrosejin 300 cc. of double distilled waterthus requires approximately minutes in its administration orapproximately 12/3 hours. The corresponding rate for otherconcentrations of solutions may be easily calculated. For example, a 10%solution formed by dissolving one gram of dextrose in 10 cc. of watermay be given as rapidly as 7.5 cc'. per minute to a person of this sameaverage weight. The data and calculations are all approximate.

If the patient weighs less than the average, there will be some slightloss on this account, but if he weighs more than the average, he merelyfails to receive the maximum dose in the shortest possible time.

Since the rate of {iow of dextrose solution injected intravenously formedical purposes must be so regulated that not more than a specifiedamount of the dextrose be injected int-o the human body in a given time,this necessitates varying the rate of injection in accordance with thepercentage strength of the solution. 7itl'1out a computing or indicatingdevice this must be laboriously figured out for cach differentinjection. Without a regulating device or valve, inaccuracies incontrolling the rate of flow are inevitable, even if the proper rate hasbeen determined by such calculation.

It has been established that when administering a dextrose solution tochildren, the rate of flow shouldbe about one-half that used inadministering to adults, and that for Vinfants, the rate should bereduced to at least one-fourth the rate employed in administering to anadult.

It thus becomes apparent, in order that the doctor will not be misled asto the results obtained, and in order not to waste the solution which isbeing injected, and yet to administer the solution as rapidly aspossible, and in order to avoid possible harmful strain on the sugarthreshold of the patients kidneys, that a device should be employed bywhich the rate of flow of the solution can be accurately regulated andbe adjustable for various strengths of solution, and that the medicatedsolution should be so administered as to give the maximum results andstill require the minimum time. It is also essential that this device beso constructed as to be surgically sterilizable.

In addition to the above, it has been found that harmful eHects followsuch injections of dextrose solutions if they are not sufficiently warm.The use of a heating device to regulate and maintain a fairly constanttemperature near to or above that of the body is, therefore, desirable.Unfavorable reactions frequently follow the injection of solutionsmedicated With salt or other therapeutic agents, as well as theinjection of citrated p blood for purposes of infusion, and a percentageof these reactions are due to the loss of heat or cooling of fluidsduring injection. It is desirable, therefore, to heat and to maintainand regulate the temperature o f all therapeutic intravenous"injections. Various heating devices have been designed for somewhatsimilar purposes, but none of these seem to embody the essential featureof being completely sterilizable by boiling, by autoclaving or byimmersion in antiseptic liquids. This is a necessity in the case of aninstrument to be used for the injection of sterilized medicatedsolutions into the veins of patients in order to avoid contamination ofthe solution and infection of the patient during the injectionoperation.

The apparatus hereinafter fully described is adapted to accomplish theseresults.

In the accompanying drawings, wherein the present preferred embodimentof my in- Vention is shown the valve for controlling the rate of flow ofthe medicated solution;

Figures 6 and 7 are views in side elevation showing opposite sides ofthe valve shown in Figure 5; and

Figure 8 is a longitudinal sectional view of a heating element adaptedto control the temperature of the medicated solution.

Referring to the preferred embodiment of the invention, and particularlyto Figure 1, there is shown a device for the intravenous injection ofmedicated solutions, comprising an infusion burette 2 and a measuringburette 3, connected through a passage in the body member 4, which ismounted upon a suitable base 5. Mounted on the body meniber 4 is a dial6, adapted to cooperate with a pointer 7, connected to a valve 8, whichcontrols the flow of solution from the bui'ettes 2 and 3 to a rubbertubing 9, which leads to a heating element 10. The opposite end of theheating element is connected by means of tubing l1 to a needle 12, whichmay be inserted into a vein of the patient.

Referring more particularly to Figures 2 to 7, inclusive, the bodymember 4 is mounted on the base 5, by means of screws 13, which alsofasten a handle 14 to the apparatus. The body member 4 is provided witha conduit 15, adapted for connection at its right hand end with aconduit 16, provided in a tube'17, connected to the infusion burette 2.The opposite or left hand end of the conduit 15 is adapted to cooperatewith the passages in a valve 8, in order to control the rate of flowfrom the burettes through the conduit 15, valve 8 and outlet 19, leadingto the heating element 10, as shown in Figure 1.

By rotating the infusion burette 2, the opening at the lower end ofconduit 16 may be-aligned with the conduit 15, thereby allowing thesolution to flow from the burette into the conduit. Hook-shaped stops 2Oand 21 are mounted on the body member 4 and are adapted to cooperatewith a lug 22 mounted on a collar 23 connected to the tube 17, in orderto limit the rotationof the burette 2 and to prevent accidentaldisplacement of the burette from the body member 4. The burette 2 ismarked, as shown, to indicate the number of cubic centimeters ofmedicated solution contained therein.

Intermediate the infusion burette and the valve 8 the body member 4 isprovided with an opening 24 adapted to receive the lower end of themeasuring burette 3 and to connect the burette with the conduit 15. Thelower portions of the infusion burette and the measuring burette whichare mounted in the body member 4 preferably are made of the'same size sothat if the measuring burette, which is made of glass, should be broken,it may be withdrawn and the infusion burette may be placed in theopening 24.

The valve 8, which controls the rate of flow of the medicated solution,is adapted to be received in an opening 25, provided in the body member4. The ,valve 8 is provided with an axial passage 26 which, when thevalve is in a position such vas to align the axial passage with theconduit 15, allows the medicated solution to How rapidly from the outlet19. The valve 8 is further provided with a circumferential groove 27,which, as shown in Figure 5, is connected at its vleft hand end with theleft hand end of the axial groove 26. The right hand end of thegroove 27terminates just short of the conduit 15. On its opposite side, the valveis provided with a second circumferential groove 28,

which is preferably of an equal depth transversel of the valvethroughout its length but W ich tapers longitudinally Yof the valve to apoint from its right hand to its left hand end (Figure 6). On the upperend of the valve, the pointer 7 is adapted to cooperate with the scale6, to indicate the rate of How of the medicated solution.

As shown in Figure 3, the scale is marked to indicate the position towhich the pointer 7 should be brought inorder 'to Hush the apparatus,and to indicate the various positions to which the pointer should bebrought in order to allow the medicated solution of different densitiesto How at different rates. The scale is marked to indicate the rates atwhich various strength solutions should be administered. As indicated, a25% dextrose solution should not be administered at a rate greater than3 cc. per minute and a 10% dextrose solution should not be administeredat a greater rate than 7.5 cc. per minute. They scale also indicates thepositions to which the pointer should be moved in order to produce thesevarious Hows. f

In Figure 8, a heating device 10 is shown which is adapted to controlthe temperature of the medicated solution. As shown, the heating deviceis made of glass and is shaped so as to provide a conduit 30, throughwhich the medicated solution flows. A heating element 31, which isformed of a material such as copper wire, is wound around the wall. 32which forms the conduit 30. Surrounding the heating element 31 and inspaced relation thereto is an outer wall 33 adapted to enclose theheating device 10, throughout the major portion of its length.

At its right hand end, the heating element 31 is connected through a lug34to an adjustable screw 35, and at its opposite end the heating elementis connected through a collar 36 to a binding post 37. At the right handend of the heating device 10 there is provided a bimetallic thermostaticelement 38 which is connected at its right hand end to the binding post39. Wires 40 and 4 1 connect the binding posts 37 and 39 to a plug 42.

In the administration of medicated solutions using the apparatus abovedescribed, the instrument is sterilized by boiling, by autoclaving or bysoakingl it in alcohol and is thereafter assembled. Hot distilled Wateris run through theI apparatus with the pointer 7 arranged in the Hushingposition indicated on the dial 6. Thereafter, the valve 8 is turned `sothat the pointer coincides with the zero position of the scale shown inFigure 3. A preheated medicated solution such, for example, as adextrose solution, is introduced into the burette 2, and the buretteturned so as to allow passage of the solution into the measuring burette3 through the conduit 15.

The valve and pointer 7 are then set at the proper point for theconcentration of dextrose solution which is being used and as soon asall air bubbles are eliminated and the How is established at the needle,the vein kmay be entered.

The medicated solution Hows from both the infusion burette 2 and themeasuring burette 3 into the conduit 15. In the Hush position, the axialassage 26 aligns with the conduit 15, thus allbwing a fast rate of Howof the solution from the device. When the Valve is in the lpositionshown in Figure 5, none of the solution passes the valve 8. However,'ifthe valve is turned in a clockwise direction as indicated by the arrow,the con duits 27 and 28 connect with the conduit 15. Flow is thenestablished from ,right to left of the apparatus shown in Figure 5through conduit 15, circumferential passage 27, axial passage 26 andcircumferential passage 28, to the outlet 19. The circumferentialpassage 28 tapers to a point (as shown in Figure 6) so that as the valveis rotated in the direction indicated by the arrow, the outlet 19 isconnected with a larger portion,r of the passage 28 and the rate of Howis thereby increased.

From the outlet 19, the medicated solution flows through the tube 9 intothe right hand end of the heating device 10, shown in Figures 1 and-8,and from the left hand end of the heating device 710, the solution Howsto the injecting needle, through the rubber tube 1l. The bimetallicelement 38, shown in Figure 8, is so constructed that when it is heatedit tends to bow downwardly. When the plug 42 is connected to a source ofelectricity and when the electrical contact 38 is in contact with thetip of the adjustable screw 35, current Hows from the -source throughthe wire 40 to the binding post 37, heating element 31, binding post 34,adjustable screw 35, bimctallic element 38, and out through the wire 41.The medicated solution flowing through the heating device therebvbecomes heated. The bimetallic element 38 is heated and bows downwardly,thus breaking Contact between the adjustable screw 35 and contact point38 and cuts off the flow of current through the heating element 31.Asthe solution cools, it cools the element 38, so that it bows upwardlyand again establishes contact with the tip of the adjustable screw 35.The temperature of the solution flowing through the heating device isgoverned by the relative position of the adjustable screw 35 andbimetallic element 38. The temperature may therefore be regulated byadjusting the screw.

If it is desired to determine if the rate of How of the solution is thesame as indicated by the pointer 7, the infusion burette 2 is rotated soas to prevent How of the solution from the burette into conduit 15. Thesolution being injected Hows entirely from the measuring burette 3 intothe conduit 15 and through the passages' previously described into avein of the patient.

Since the capacity of the measuring bu rette 3 is small as compared withthe capacity of the infusion burette Q, the droi in the level of thesolution in the measuring ,burette is rapid and may be easily observed.The rate of flow may be easily determined by timing with a Watch, thusgiving a check on the flow indicated by the pointer 7.

Although any suitable material which is not attacked by the medicatedsolution may be employed to form the apparatus shown in Figure 2, Iprefer to use either Monel metal, which'is approximately 65% nickel and35% copper, or a chromium, nickel alloy of iron, the chromium runningfrom 17 to 20% and the nickel from T to 10 C/v. If desired, either ofthese materials may be nickel plated.

It is to be understood that the form of the invention herewith shown anddescribed is to be taken as the preferred embodiment of the same, andthat the invention is not so limited but may be otherwise embodiedWithin the scope of the following claims.

I claim:

l. device of the character described comprising a body portion providedWith a conduit, an infusion burette rotatably mounted in said bodyportion and adapted upon rotation to either establish or cut offcommunica tion between said burette and the conduit, a valve arranged insaid body portion and adapted to cooperate with the conduit in order tocontrol the rate of flow of the solution from the device, and means fordetermining the rate of flow of the solution from the device Withoutinterrupting its flow.

2. A device of the character described comprising a body provided withconduit, an infusion burette rotatably mounted in said body portion andadapted upon rotation to either establish or cut olf communicationbetween said burette and the conduit, a valve arranged in said bodyportion and adapted to cooperate With the conduit in order to controlthe rate of flow of the solution from the device, and a measuringburette connected to the conduit for determining he rate of iioW of thesolution `from the device Without interrupting its ow When saidinfusionI burette is in a position to out 0H flow from Said infusionburette to the conduit.

3. In the method of injecting medicatedv solutions in which an infusionburette and a measuring burette are employed, the step of determiningthe rate of flow of the solution which comprises causing the solution toflow onlyvfrom the measuring burette, and tim ing the flow from themeasuring burette.

4. An apparatus for injecting medicated solutions, comprising a bodyportion provided with a conduit, an infusion burette and a measuringburette communicating with the conduit, a valve for controlling the flowof solution in the conduit, and means for causing all the solutionpassing through said valve to be supplied from said measuring burettewhereby the rate oflow through the valve can be determined by observingthe measuring burette.

5. An apparatus for injecting medicated solutions comprising a bodyportion provided With a conduit, an infusion burette and a measuringburette, each connected through valves with the conduit, and a conduitvalve for controlling the flow of solution in the conduit, thearrangement being such that all of the solution passing through saidconduit valve may be supplied from said measuring buiette whereby therate of flow through the valve can be determined by observing themeasuring burette.

In testimony whereof I have hereunto set my hand.

PAUL TITUS.'

